Baltimore Orioles second baseman Bill Ripken, 26, coming off his best season, signed a one-year contract for $700,000 yesterday rather than go to arbitration.

He led the Orioles in batting at .291 and in doubles with 28, plus he tied for the AL lead with 17 sacrifice bunts. In his fifth season, he raised his batting average 52 points over the previous season, second-best improvement in the AL. He had a personal high for consecutive errorless games, 53, and made eight errors all season.

California Angels first baseman Wally Joyner became a two-time arbitration winner when arbitrator Gil Vernon picked Joyner's salary figure of $2.1 million over the Angels' figure of $1.65 million.

The number filed by the Angels would have been a $100,000 pay cut from his '90 salary of $1.75 million, which was also determined when Joyner prevailed in an arbitration hearing last winter after the Angels filed at $1,225,000.

A stress fracture in his right kneecap limited Joyner to 83 games last season. He batted .268 with eight home runs and 41 RBI.

Third baseman Ken Caminiti and the Astros agreed to a one-year deal worth $665,000, a raise of $425,000. He had sought $715,000 while the Astros had offered $585,000. He hit .242 with four home runs and 51 RBI last season.

San Diego Padres right fielder Tony Gwynn had a 4 1/2-hour operation to remove a benign tumor from his mouth and is resting comfortably in a hospital in La Jolla, Calif.

George Foster, the last NL player to hit 50 home runs in a season, will be a volunteer assistant coach at Sacred Heart University in Fairfield, Conn.